Digital broadcast signal processing method and device

ABSTRACT

The present application relates to a device and method for processing digital broadcast signals comprising three-dimensional images. According to one embodiment of the present invention, the digital broadcast signal processing method comprises the steps of: encoding a video stream of a two dimensional reference image; encoding a video stream of an additional image, for generating a binocular-disparity three-dimensional image together with the encoded two dimensional reference image; generating signaling information such that the video stream of the encoded additional image is processed only in a three-dimensional image signal receiver; generating a first broadcast signal comprising the video stream of the encoded reference image; generating a second broadcast signal comprising the video stream of the encoded additional image and the signaling information; and respectively sending the first broadcast signal and the second broadcast signal over different channels.

This application is a 35 USC §371 National Stage entry of InternationalApplication No. PCT/KR2012/006888, filed Aug. 29, 2012, and claimspriority to U.S. Provisional Application No. 61/529,253 filed Aug. 31,2011, both of which are hereby incorporated by reference in itsentirety.

TECHNICAL FIELD

The present invention relates to a device and method for processing adigital broadcast signal including three-dimensional (3D) video, andmore particularly, to a processing device and method for transmittingand receiving a digital broadcast signal including 3D video via aplurality of channels or a plurality of paths and displaying the 3Dvideo.

BACKGROUND ART

As 3D televisions (3DTV) have come into widespread use, 3D video contenthas come into widespread use and 3D video content has been transmittedthrough a digital broadcast.

In general, 3D video provides a stereoscopic effect using the principleof stereovision. Since a human feels a perspective effect throughbinocular parallax due to an interval between the eyes spaced apart fromeach other by about 65 mm, 3D video is provided such that a left eye anda right eye view respective plan images, thereby providing astereoscopic effect and a perspective effect.

Examples of a 3D video display method include a stereoscopic method, avolumetric method, a holographic method, etc. In the stereoscopicmethod, a left view image to be viewed by a left eye and a right viewimage to be viewed by a right eye are provided and the left eye and theright eye respectively view the left view image and the right view imagethrough polarized glasses or a display device, thereby perceiving a 3Dvideo effect.

In case of stereoscopic 3D video content, when two similar videos ofdifferent views are transmitted, a receiver uses a method of displaying3D video using the two videos. At this time, the two similar videos ofthe different views may be transmitted via an existing broadcast channelor separately transmitted via the existing broadcast channel and aseparate transmission channel. In this case, the receiver should receivesignal information of two videos forming a pair in order to display thetwo videos as 3D video. When such information is not received, aleft-view image and a right-view image forming 3D video may not bedistinguished such that the 3D video is not restored. In addition, it isnot possible to check a synchronization time of the left-view image andthe right-view image and when 3D video can be displayed.

DISCLOSURE Technical Problem

An object of the present invention devised to solve the problem lies ina device and method for receiving a digital broadcast signal includingsignal information for displaying 3D video and displaying the 3D video.

Technical Solution

The object of the present invention can be achieved by providing adigital broadcast signal processing method for providing stereoscopicthree-dimensional (3D) video including encoding a video stream oftwo-dimensional (2D) primary video, encoding a video stream of secondaryvideo for generating binocular-parallax 3D video together with theencoded video stream of the 2D primary video, generating signalinginformation such that the encoded video stream of the secondary video isonly processed in a 3D video signal receiver, generating a firstbroadcast signal including the encoded video stream of the primaryvideo, generating a second broadcast signal including the encoded videostream of the secondary video and the signaling information andtransmitting the first broadcast signal and the second broadcast signalvia different channels.

In the digital broadcast signal processing method according to thepresent invention, the generating the signaling information may includegenerating signaling information requesting that a 2D video signalreceiver should not recognize the encoded video stream of the secondaryvideo.

In the digital broadcast signal processing method according to thepresent invention, the generating the signaling information may includeexcluding a channel, via which the second broadcast signal istransmitted, from a channel map.

In the digital broadcast signal processing method according to thepresent invention, the generating the signaling information may includegenerating signaling information for preventing a 2D video signalreceiver from recognizing the encoded video stream of the secondaryvideo.

In the digital broadcast signal processing method according to thepresent invention, the generating the signaling information may includelimiting signaling information of a stream transmitted by the secondbroadcast signal to only a PAT and deleting a program_loop or setting aprogram_number to 0.

In another aspect of the present invention, provided herein is a digitalbroadcast signal processing device for providing stereoscopicthree-dimensional video including a first video encoder for encoding avideo stream of two-dimensional (2D) primary video, a second videoencoder for encoding a video stream of secondary video for generatingbinocular-parallax 3D video together with the encoded video stream ofthe 2D primary video, an SI processor for generating signalinginformation such that the encoded video stream of the secondary video isonly processed in a 3D video signal receiver, a first system encoder forgenerating a first broadcast signal including the encoded video streamof the primary video, a second system encoder for generating a secondbroadcast signal including the encoded video stream of the secondaryvideo and the signaling information and a transmission unit fortransmitting the first broadcast signal and the second broadcast signalvia different channels.

In the digital broadcast signal processing device according to thepresent invention, the SI processor may generate signaling informationrequesting that a 2D video signal receiver should not recognize theencoded video stream of the secondary video.

In the digital broadcast signal processing device according to thepresent invention, the SI processor may exclude a channel, via which thesecond broadcast signal is transmitted, from a channel map.

In the digital broadcast signal processing device according to thepresent invention, the SI processor may generate signaling forpreventing a 2D video signal receiver from recognizing the encoded videostream of the secondary video.

In the digital broadcast signal processing device according to thepresent invention, the SI processor may limit signaling information of astream transmitted by the second broadcast signal to only a PAT anddelete a program_loop or set a program_number to 0.

Advantageous Effects

According to the digital broadcast signal reception device of thepresent invention, the following effects are obtained.

According to one embodiment of the present invention, it is possible toreceive a digital broadcast signal and to display a 3D video signal.

According to one embodiment of the present invention, it is possible toreceive a digital broadcast signal and to check when a 3D video signalcan be displayed.

According to one embodiment of the present invention, it is possible toreceive a digital broadcast signal and to obtain accuratesynchronization information.

According to one embodiment of the present invention, it is possible tosupport backward compatibility with an existing broadcast signalreception device.

DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram showing a combination of video elements included in3D video according to one embodiment of the present invention;

FIG. 2 is a diagram showing a digital broadcast signal reception deviceaccording to one embodiment of the present invention;

FIG. 3 is a diagram showing a syntax structure of an EIT including anevent_enhancement_descriptor( ) according to one embodiment of thepresent invention;

FIG. 4 is a diagram showing a syntax structure of anevent_enhancement_descriptor( ) according to one embodiment of thepresent invention;

FIG. 5(a) is a diagram showing a combined_service_type according to oneembodiment of the present invention;

FIG. 5(b) is a diagram showing an enhancement_type according to oneembodiment of the present invention;

FIG. 6(a) is a diagram showing a sync_type according to one embodimentof the present invention;

FIG. 6(b) is a diagram showing an enhancement_stream_format according toone embodiment of the present invention;

FIG. 6(c) is a diagram showing an enhancement_stream_sampling_factoraccording to one embodiment of the present invention;

FIG. 7 is a diagram showing a syntax structure of a PMT including anevent_enhancement_descriptor( ) according to one embodiment of thepresent invention;

FIG. 8 is a diagram showing a syntax structure of aprogram_enhancement_descriptor( ) according to one embodiment of thepresent invention;

FIG. 9 is a diagram showing a syntax structure of a TVCT including achannel_enhancement_descriptor( ) according to one embodiment of thepresent invention;

FIG. 10 is a diagram showing a syntax structure of achannel_enhancement_descriptor( ) according to one embodiment of thepresent invention;

FIG. 11 is a diagram showing a syntax structure of an SDT including aservice_enhancement_descriptor( ) according to one embodiment of thepresent invention;

FIG. 12 is a diagram showing a syntax structure of aservice_enhancement_descriptor( ) according to one embodiment of thepresent invention;

FIG. 13 is a diagram showing a syntax structure of an EIT including anevent_enhancement_descriptor2( ) according to one embodiment of thepresent invention;

FIG. 14 is a diagram showing a syntax structure of anevent_enhancement_descriptor2( ) according to one embodiment of thepresent invention;

FIG. 15 is a diagram showing a new combination of stream_content and acomponent_type according to one embodiment of the present invention;

FIG. 16 is a diagram showing signaling for requesting that an existingreceiver should not recognize secondary video in an ATSC PSIPenvironment according to one embodiment of the present invention;

FIG. 17 is a diagram showing signaling for requesting that an existingreceiver should not recognize secondary video in a DVB-SI environmentaccording to one embodiment of the present invention;

FIG. 18 is a diagram showing signaling for preventing an existingreceiver from recognizing secondary video in an ATSC PSIP environmentaccording to one embodiment of the present invention;

FIG. 19 is a diagram showing signaling for preventing an existingreceiver from recognizing secondary video in a DVB-SI environmentaccording to one embodiment of the present invention;

FIG. 20 is a diagram showing a transport_packet( ) according to oneembodiment of the present invention;

FIG. 21 is a diagram showing an adaptation_field( ) according to oneembodiment of the present invention;

FIG. 22(a) is a diagram showing the syntax of avideo_frame_info_data_byte according to one embodiment of the presentinvention;

FIG. 22(b) is a diagram showing the meaning of video_frame_infoaccording to a setting value of a frame_info_type according to oneembodiment of the present invention;

FIG. 23 is a diagram showing a video level synchronization methodaccording to one embodiment of the present invention;

FIG. 24 is a diagram showing a digital broadcast reception deviceaccording to one embodiment of the present invention; and

FIG. 25 is a diagram showing a view synthesis and synchronizationoperation according to one embodiment of the present invention.

BEST MODE

Hereinafter, the embodiments of the present invention will be describedin detail with reference to the accompanying drawings although thepresent invention is not limited by the embodiments.

Although the terms used in the present invention are selected fromgenerally known and used terms, terms used herein may be variabledepending on operator's intention or customs in the art, appearance of anew technology, or the like. In addition, some of the terms mentioned inthe description of the present invention have been selected by theapplicant at his or her discretion, the detailed meanings of which aredescribed in relevant parts of the description herein. Furthermore, itis required that the present invention is understood, not simply by theactual terms used but by the meanings of each term lying within.

A 3D video display method may include a stereoscopic method consideringtwo views and a multiple view image method (a multi-view method)considering three or more views. A conventional single view image isreferred to as a monoscopic image method.

The stereoscopic method uses a pair of images, that is, a left viewimage (hereinafter, referred to as a left image) and a right view image(hereinafter, referred to as a right image), acquired by capturing thesame subject using a left camera and a right camera spaced apart fromeach other by a fixed distance, or a pair of a primary image and asecondary image. Hereinafter, the left and right images and the primaryand secondary images are included in a stereoscopic 3D image and mayhave the same meaning. The multi-view method uses three or more imagesacquired by capturing the same subject using three or more camerashaving constant distances or angles. Hereinafter, although thestereoscopic method is described in one embodiment of the presentinvention, the present invention is applicable to a multi-view method.

The stereoscopic method according to the present invention includes aside-by-side mode, a top-bottom mode, a checkerboard mode, etc. In theside-by-side mode, a left image and a right image are ½ down-sampled ina horizontal direction, one sampled image is located in a left regionand the other sampled image is located in a right region, therebyconfiguring one stereoscopic image. In the top-bottom mode, a left imageand a right image are ½ down-sampled in a vertical direction, onesampled image is located in a top region and the other sampled image islocated in a bottom region, thereby configuring one stereoscopic image.In the checker board mode, a left image and a right image are ½down-sampled to be crossed in vertical and horizontal directions suchthat two images are combined into one image. However, the stereoscopicmethod according to the present invention is not limited to the aboveexamples. For example, in a method of providing a 3D video service via aplurality of channels described in the present invention, two imageshaving full resolutions may be transmitted and received without adown-sampling operation to provide a 3D video service.

The stereoscopic method requires additional signal information forcoupling a left image and a right image or a primary image and asecondary image included in the same 3D video.

FIG. 1 is a diagram showing a combination of video elements included in3D video according to one embodiment of the present invention.

When an element configuring a 3D program is composed of two or morevideo elements, these video elements may include a primary video elementand a secondary video element. The primary image element includestwo-dimensional (2D) stream coded by motion picture experts group-2(MPEG-2) or AVC/H.264 or phase1 3DTV video which is frame-compatible 3Dvideo coded by AVC/H.264.

The secondary image element includes depth information (depth map ordisparity map), multiview video coding (MVC) extension, secondary image2D stream in a 3D system using a dual independent stream method, such asMPEG-2 or AVC/H.264, and an enhancement signal for Phase1 3DTV video.The depth map may optionally include occlusion information ortransparency information.

FIG. 2 is a diagram showing a digital broadcast signal reception deviceaccording to one embodiment of the present invention. The digitalbroadcast reception device according to the present invention mayinclude a plurality of stream demultiplexers 21 and 22, a plurality ofsystem decoders 23 and 24, a plurality of video decoders 25 and 26, asynchronizer 27, a view rendering unit 28 and an output formatter 29.Here, the view rendering unit 28 operates when depth information (depthmap or disparity map) is input as a secondary image element.

The demultiplexers 21 and 22 receive a broadcast stream including aprimary video element and a secondary video element and demultiplex theprimary video element and the secondary video element. At this time, thedemultiplexer for the primary video may also extract an audio elementand data.

The extracted primary video element and the secondary video element arerespectively input to the system decoders 23 and 24 and the systemdecoders 23 and 24 extract synchronization information therefrom. Theacquired synchronization information is used for matching between theprimary video and the secondary video independently decoded by the videodecoders 25 and 26.

The decoded primary video element is independently output as primaryvideo to display a 2D video signal.

The synchronizer 27 synchronizes the primary video and the secondaryvideo and outputs the synchronized video to the view rendering unit 28.The view rendering unit 28 is enabled when the secondary video elementis depth information and renders the secondary video based on theprimary video and the depth information. At this time, when thesecondary video element is depth information, the secondary videoelement cannot provide video but serves as secondary view video bycombining the primary video and the depth information by the viewrendering unit 28.

When the secondary video element is not depth information but is animage, for example, a 2D secondary video stream in a 3D system using adual independent stream method such as MPEG-2 or AVC/H.264, the viewrendering 28 may not be enabled.

The secondary video (right image or left image) and the primary video(left image or right image) are output on the 3D display via the outputformatter 29 as 3D video.

When the primary video is received via a terrestrial wave, the videobecomes a view configuring stereoscopic 3D video and the received videois combined with secondary video received via a separate channel,thereby outputting stereoscopic 2D video.

In the following embodiments, assume a transmission scenario that theprimary video (e.g., 2D video) is received via an existing broadcastchannel, the secondary video (e.g., enhancement video or depthinformation) is received via a separate channel and the primary videoand the secondary video are synchronized in real time.

In a process of outputting 3D video, previously received secondary videomay be linked with primary video received in real time to render 3Dvideo.

In order to link the primary video and the secondary video to output a3D video signal, the following considerations are present.

First, signaling of linkage information of primary video and secondaryvideo is necessary. For example, presence signaling which is informationindicating presence of the secondary video linked with the primaryvideo, location signaling which is information about a path (location)of the secondary video linked with the primary video,synchronization/coupling mode signaling which is information about asynchronization or linkage method of the secondary video linked with theprimary video, available time signaling which is information about whenthe secondary video linked with the primary video may be received,format/codec signaling which is information about the format or codec ofthe secondary video linked with the primary video and depth rangesignaling for providing depth range information of secondary video and amethod of transmitting several pieces of depth information or secondaryvideo in order to provide a 3D video signal having various depth rangesare necessary.

Next, frame level synchronization level for linking primary video andsecondary video is necessary. For example, video level signaling ortransport stream level signaling is necessary.

In association with receiver operation, as a method of receiving,reproducing and storing secondary video linked with primary video and amethod of supporting various depth modes, several secondary videoshaving multiple depth maps (depth track)/different depth ranges need tobe considered.

In association with a method of preventing all the above-describedinformation from having influence on a normal operation of a 2D or 3Dreceiver, signaling considers a method of acquiring access informationof enhancement data including depth data via a channel for receivingprimary video, the channel for receiving the enhancement data(hereinafter, the enhancement data includes depth data) cannot providean independent service, and signaling information provides informationabout the enhancement data. Additionally, linkage information of a 2Dvideo reception channel may be provided. An existing receiver shouldunmeaningfully transmit and receive signaling information.

Hereinafter, a descriptor for signaling enhancement data via an SIsection will be defined. For convenience, the descriptor does notinclude a loop but may transmit multiple enhancement data according tocircumstance. At this time, in the descriptor, the field is repeated bythe number of transmitted enhancement data streams. In particular, thiscorresponds to depth control implementation via multiple depth maptransmission.

First, a signaling method using an EIT of an ATSC PSIP will bedescribed.

FIG. 3 is a diagram showing a syntax structure of an EIT including anevent_enhancement_descriptor( ) according to one embodiment of thepresent invention.

Signaling of enhancement data linked with this event is performed usinga descriptor at an event level of the EIT.

A table_id field is an 8-bit field, is set to 0xCB, and indicates thatthe section belongs to the EIT.

A section_syntax_indicator field is a 1-bit field and the value thereofis set to 1. This means that the section follows a generic sectionsyntax after the section length field.

A private_indicator field is a 1-bit field and is set to 1.

A section_length field is a 12-bit field and indicates the number ofbytes from a next field of this field to a section including a CRC_32field. The value of this field does not exceed 4093.

A source_id field is a 16-bit field and indicates a source_id of avirtual channel for sending an event described in this section.

A version_number field is a 5-bit field and indicates the version numberof EIT-i. The version number is incremented by one (modulo 32) if anyfield of EIT-i is changed. If i and j are different, the version numberof EIT-i and the version number of EIT-j are unrelated. This field hasthe same value as an MGT.

A current_next_indicator field is a 1-bit indicator and is always set to1 with respect to the EIT section. Currently, the EIT is alwaysapplicable.

A section_number field is an 8-bit field and indicates the number ofsections.

A last_section_number field is an 8-bit field and indicates the numberof the last section.

A protocol_version field serves to allow a table type different fromthat defined in the current protocol in the future. In the currentprotocol, only 0 is valid. A value other than 0 will be structurallyused in the subsequent version for another table.

A num_events_in_section field is an 8-bit field and indicates the numberof the event in the EIT section and indicates that an event is notdefined in this section if the value thereof is 0.

An event_id field is a 14-bit field and indicates the ID of thedescribed event. This is used as a part of ETM_id.

A start_time field is a 32-bit field and indicates a start time of anevent in GPS seconds after 1980.1.6. 00:00:00 UTC. In any virtualchannel, the value of the start_time cannot be smaller than the end_timeof a previous event. Here, the end_time is defined as a value obtainedby adding the length of the event length_in_seconds to the start_time ofthe event.

An ETM_location field is a 2-bit field and indicates presence andlocation of an extended text message (ETM).

A length_in_seconds field indicates the duration of this event inseconds.

A title_length field indicates the length of title_text( ) in bytes andindicates that there is no title of the event if the value thereof is 0.

A title_text( ) field indicates the title of the event of multiplestring structure formats.

A descriptors_length field indicates the total length of the followingevent descriptor in bytes. 0 or more descriptors are included in the EITby for-loop included in descriptor( ). The type of the descriptordefined to be used in the EIT may include thecontent_advisory_descriptor( ), the caption_service_descriptor( ), theAC-3 audio_stream_descriptor( ), etc. The event_enhancement_descriptor() of the present invention may be included in the descriptor( ).

A CRC_32 field is a 32-bit field and indicates a CRC value for a zerooutput of a register within a decoder.

FIG. 4 is a diagram showing a syntax structure of anevent_enhancement_descriptor( ) according to one embodiment of thepresent invention.

The event_enhancement_descriptor( ) of the present invention includes acombined_service_type, an enhancement_type, an enhancement_right_flag, async_type, an enhancement_stream_format, anenhancement_stream_sampling_factor, an avail_time_start, a linked_TSID,a linked_program_number, a linked_elementary_PID, aninternet_linkage_information, a disparity_near and a disparity_far.

FIG. 5(a) is a diagram showing a combined_service_type according to oneembodiment of the present invention. The combined_service_type is afield indicating a service type provided when componentsreceived/transmitted via two or more separate paths/channels arecombined, that is, means the type of a final service provided bycombining the event and enhancement data received via a locationspecified in this descriptor. This indicates a 2D scalable video serviceif the value of combined_service_type is 0x0, indicates a 3Dstereoscopic video service if the value of combined_service_type is 0x1,indicates a 3D multi-view service if the value of combined_service_typeis 0x2, and indicates a ultra definition (UD) video service if the valueof combined_service_type is 0x3. Hereinafter, in the present invention,the 3D stereoscopic service in the case in which thecombined_service_type is 0x1 will be focused upon.

The enhancement_right_flag indicates the left view/right view of thevideo when the view of the stereoscopic 3D video service is renderedusing the enhancement data. If the value thereof is “1”, enhancementdata or the view acquired via the enhancement data is right video.

FIG. 5(b) is a diagram showing an enhancement_type according to oneembodiment of the present invention. The enhancement_type indicates thetype of the path via which the enhancement data of this event istransmitted. For example, there are a terrestrial channel, the Internet,etc.

If the enhancement_type is 0x0, then this indicates that this eventcontains all necessary components of a service. This means thatenhancement data is contained as the component of this event and isreceived.

If the enhancement_type is 0x1, then the enhancement data is receivedvia a channel different from a channel via which this event is receivedand the type of the reception path is equal to that of this event. Forexample, if the event is a terrestrial wave, the enhancement data isalso received via another channel of a terrestrial wave. Detailed pathinformation of the enhancement data uses a linked_TSID field and alinked_program_number field.

If the enhancement_type is 0x2, then this indicates that this eventincludes only the enhancement data and essential data is transmitted viathe same type of path. That is, both the enhancement data and theessential data are received via the terrestrial wave. Similarly,detailed path information of the essential data uses a linked TSI fieldand a linked_program_number field.

If the enhancement_type is 0x3, then this indicates that the enhancementdata of this event is received via the Internet. Path information foraccessing the enhancement data uses an internet_linkage_informationfield.

FIG. 6(a) is a diagram showing a sync_type according to one embodimentof the present invention. The sync_type indicates information about asynchronization and synthesis method for transmission of the componentof the event and the enhancement data.

If the sync_type is 0x0, then the component of the event and theenhancement data are simultaneously transmitted. This may be referred toas synchronized transmission.

If the sync_type is 0x1, then the enhancement data is transmitted laterthan the event. For normal 3D video viewing, this event is recorded andthen is linked or synthesized with the enhancement data received later.

If the sync_type is 0x2, then the enhancement data is transmittedearlier than the event. For normal 3D video viewing, the component ofthe event received in real time is linked/synthesized with the alreadyreceived/stored enhancement data.

If the sync_type is 0x3, then this is similar to the case in which thesync_type is 0x1 but synchronized transmission of the enhancement datais also possible.

If the sync_type is 0x4, then this is similar to the case in which thesync_type is 0x2 but synchronized transmission of the enhancement datais also possible.

FIG. 6(b) is a diagram showing an enhancement_stream_format according toone embodiment of the present invention. The enhancement_stream_formatindicates information about the data format, codec, etc. of theenhancement data of this event. Hereinafter, in the presentspecification, 0x25 and 0x26 corresponding to the cases of transmittingdepth/disparity data will be focused upon.

FIG. 6(c) is a diagram showing an enhancement_stream_sampling_factoraccording to one embodiment of the present invention. Theenhancement_stream_sampling_factor means the resolution of theenhancement data and indicates the sampling factor of the enhancementdata in width and height as compared to the video stream (primary video)of this event. If the value thereof is 0x00, this indicates that theenhancement data has the same resolution as the primary video and, ifthe value thereof is 0xXY, this indicates that the sampling factor ofthe enhancement data is 1/(X+1) of the primary video in width and is1(Y+1) of the primary video in height. For example, in case of thedepth/disparity map having a size of ¼ in width and a size of ⅛ inheight, this field has a value of 0x37.

An avail_time_start field means a start time when the enhancement datacurrently configuring 3D video content together with the component ofthe event is transmitted. The avail_time start field is a 32-bit fieldand indicates a start time of the event in GPS seconds after 1980.1.6.00:00:00 UTC. If the value of this field is 0, the enhancement data isalways available.

A linked_TSID field means the transport_stream_id value of the transportstream including the enhancement data.

A linked_program_number field indicates the program_number value of aprogram/channel including the enhancement data. That is, a streamincluding the enhancement data may be uniquely defined using thelinked_TSID and the linked_program_number.

A linked_elementary_PID field may include an elementary PID value of theenhancement data in the event_enhancement_descriptor( ) in addition tothe linked_TSID and the linked_program_number.

An internet_linkage_information field provides information about theenhancement data transmitted via the Internet and may include a fieldindicating whether an IP address is 32 bits or 128 bits, an IP address,a port number, additional information such as a URI of the stream and anavailable time slot. At this time, the available time slot may include astart time and an expiration time and may overlap the avail_time_startfield.

A disparity_near field and a disparty_far field indicate the depth rangeif the enhancement data is depth information (disparity/depth map).These indicate disparity values corresponding to object points nearestto or farthest from the user.

In the above descriptor, signaling of multiple enhancement streams ispossible. In the descriptor, n enhancement streams may be signaled usinga loop.

Next, a signaling method using a program map table (PMT) will bedescribed.

FIG. 7 is a diagram showing a syntax structure of a PMT including anevent_enhancement_descriptor( ) according to one embodiment of thepresent invention.

The PMT provides mapping between a program number and a program element.At a program level (a first descriptor loop) or an ES level (a seconddescriptor loop) of the PMT, enhancement data linked with the program orthe program element is signaled using a descriptor.

The PMT includes the following fields.

A table_id field is an 8-bit field and TS_program_map_section is alwaysset to a value of 0x02.

A section_syntax_indicator field has 1 bit and the value thereof is setto 1.

A section_length field has 12 bits and the first two bits are 00. Thisfield indicates the number of bytes of the section and indicates thelength from a next field to CRC. The value of this field does not exceed1021.

A program_number field has 16 bits and indicates to which a programprogram_map_PID is applied. Definition of one program is transmitted byonly one TS_program_map_section. This indicates that program definitioncannot exceed 1016.

A version_number field indicates the version of a virtual channel. Thisfield is incremented by one whenever the VCT is changed. If the versionvalue reaches 31, a next version value becomes 0. The value of thisfield is necessarily equal to the value of the same field of an MGT.

A current_next_indicator field has 1 bit and the value thereof is set to1 if the VCT is currently applicable. If the value thereof is set to 0,this indicates that the VCT is not applicable and a next table is valid.

The value of a section_number field is set to 0x00.

The value of a last_section_number field is set to 0x00.

A PCR_PID field has 13 bits and indicates a PID of a TS including a PCRfield which is valid with respect to the program described by theprogram number.

A program_info_length field has 12 bits and the first two bits have avalue of 00. The remaining 10 bits indicate the descriptor which followsthis field in bytes.

A stream_type field has 8 bits and indicates the type of a programelement transmitted by packets having a PDI value of a base PID.

Elementary_PID has 13 bits and indicates a PID of a TS including anassociated program element.

An ES_info_length field has 12 bits and the first two bits are 00. Theremaining 10 bits indicates the descriptor which follows this field inbytes.

A CRC_32 field indicates a CRC value for a zero output of a registerwithin a decoder.

FIG. 8 is a diagram showing a syntax structure of aprogram_enhancement_descriptor( ) according to one embodiment of thepresent invention.

The program_enhancement_descriptor( ) of the present invention includesa combined_service_type, an enhancement_type, an enhancement_right_flag,sync_type, an enhancement_stream_format, anenhancement_stream_sampling_factor, a linked_TSID, alinked_program_number, a linked_elementary_PID, aninternet_linkage_information, a disparity_near and a disparity_far.

The program_enhancement_data_descriptor provides information aboutenhancement data linked with the program for implementing a 3D videoservice. At this time, the provided information indicates linkage withthe program.

The enhancement_type indicates the type of path via which theenhancement data for this program is transmitted. The meaning of thevalue of this field is equal to that defined in theevent_enhancement_descriptor( ) but is different therefrom in that thisfield is not applied in event units but is applied in program units. Thefunctional meanings of the other fields are equal those defined in theevent_enhancement_descriptor( ).

The linked_elementary_PID is not essential and may be omitted accordingto the embodiment.

Next, a signaling method using a terrestrial virtual channel table(TVCT) of an ATSC PSIP will be described.

FIG. 9 is a diagram showing a syntax structure of a TVCT including achannel_enhancement_descriptor( ) according to one embodiment of thepresent invention.

The TVCT includes attributes of virtual channels included in a transportstream in an ATSC PSIP.

Information included in the TVCT will be described.

The value of a table_id field indicates the type of the table section.In order to indicate the TVCT, the value thereof shall be 0xC8.

A section_syntax_indicator field has 1 bit and the value thereof isfixed to 1.

A private_indicator field is set to 1.

A section_length field has 12 bits and the first two bits are 00. Thisfield indicates the number of bytes of the section and indicates thelength from a next field to CRC. The value of this field does not exceed1021.

A transport_stream_id has 16 bits and indicates an MPEG-2 transportstream (TS) ID. By this field, this TVCT is distinguished from anotherTVCT.

A version_number field indicates the version of a virtual channel. Thevalue of this field is incremented by one whenever the VCT is changed.If the version value reaches 31, a next version value becomes 0. Thevalue of this field is necessarily equal to the value of the same fieldof an MGT.

A current_next_indicator field has 1 bit and the value thereof is set to1 if the VCT is currently applicable. If the value thereof is set to 0,this indicates that the VCT is not applicable and a next table is valid.

A section_number field indicates the number of sections. The value of afirst section of the TVCT is 0x00 and the value thereof is incrementedby one per additional section.

A last_section_number field indicates the number of the last section,that is, the number of the section having a highest section_number inthe TVCT.

A protocol_version field serves to allow another table type differentfrom that defined in the current protocol in the future. In the currentprotocol, only 0 is valid. A value other than 0 will be structurallyused in the subsequent version for another table.

A num_channels_in_section field indicates the number of virtual channelsin the VCT section. The value thereof is restricted by the sectionlength.

A short_name field indicates the name of the virtual channel.

A major_channel_number field has 10 bits and indicates a major channelnumber of a virtual channel defined in corresponding order within afor-loop. Each virtual channel includes a major channel number and aminor channel number. The user may use the major channel number alongwith the minor channel number with respect to the virtual channel. Themajor channel number has values of 1 to 99 and the major/minor channelnumber pair does not have a repeated value within the TVCT.

The minor_channel_number field has 10 bits and has values of 0 to 999.The minor channel number functions as a two-part channel number alongwith the major channel number. If a service type isATSC_digital_television or ATSC_audio_only, the minor channel number hasvalues of 1 to 99. The major/minor channel number pair does not have arepeated value within the TVCT.

A modulation_mode field indicates a modulation mode of a transportcarrier associated with the virtual channel.

The value of a carrier_frequency field is 0. The carrier frequency canbe confirmed using this field.

A channel_TSID field has values of 0x0000 to 0xFFFF and is an MPEG-2TSID associated with a TS for transferring an MPEG-2 program referred toby this virtual channel.

A program_number field associates a virtual channel defined in the TVCTwith an MPEG-2 PROGRAM ASSOCIATION and TS PROGRAM MAP table.

An ETM_location field indicates presence and location of an extendedtext message (ETM).

An access_controlled field is a 1-bit Boolean flag, indicates an eventassociated with the virtual channel is accessed and controlled if thevalue thereof is 1, and indicates that access is not limited if thevalue thereof is 0.

A hidden field is a 1-bit Boolean flag. If the value thereof is 1, evenwhen the user directly inputs the number, access is not allowed. Ahidden virtual channel is skipped if the user performs channel surfingand appears as not being defined.

A hide_guide field is a Boolean flag. If the value thereof is set to 0with respect to a hidden channel, the virtual channel and event thereofmay be displayed on an EPG display. If a hidden bit is not set, thisfield is ignored. Accordingly, a non-hidden channel and an event thereofbelong to the EPG display regardless of the state of the hide_guide bit.

A service_type field confirms the type of a service sent by the virtualchannel.

A source_id field confirms a programming source associated with thevirtual channel. The source may be any one of video, text, data or audioprogramming. Source id 0 is a reserved value, has a unique value withina TS for sending the VCT from 0x0001 to 0x0FFF, and has a unique valuewithin a region level from 0x1000 to 0xFFFF.

A descriptors_length field indicates the length of the descriptor whichfollows the virtual channel in bytes.

A descriptor need not be included in descriptor( ) or one or moredescriptors may be included in descriptor( ).

An additional_descriptors_length field indicates the total length of afollowing VCT descriptor list in bytes.

A CRC_32 field indicates a CRC value for a zero output of a registerwithin a decoder.

At a virtual channel level of the TVCT, using the descriptor, signalinformation about the enhancement data linked with the component of thevirtual channel for providing a 3D video service is signaled. Thisinformation indicates linkage with the channel.

FIG. 10 is a diagram showing a syntax structure of achannel_enhancement_descriptor( ) according to one embodiment of thepresent invention.

The channel_enhancement_descriptor( ) of the present invention includesa combined_service_type, an enhancement_type, an enhancement_right_flag,a sync_type, an enhancement_stream_format, anenhancement_stream_sampling_factor, a linked_TSID, alinked_program_number, a linked_service_a linked_elementary_PID, aninternet_linkage_information, a disparity_near and a disparity_far.

The enhancement_type indicates the type of a path via which theenhancement data for the virtual channel is transmitted. For example,there are a terrestrial channel, the Internet, etc. The meaning of thisfield is equal to the above-described definition but is differenttherefrom in that this field is not applied in event units or programunits but is applied in virtual channel units.

The linked_channel_TSID indicates a transport_stream_id value of aprogram/channel including a stream to be linked with the presentprogram/channel in order to provide a complete 3D video service.

The linked_channel_program_number indicates a program_number value of aprogram/channel including a stream to be linked with the presentprogram/channel in order to provide a complete 3D video service.

The linked_major_channel_number indicates a major_channel_number of achannel including a stream to be linked with the present program/channelin order to provide a complete 3D video service.

The linked_minor_channel_number indicates a minor_channel_number of achannel including a stream to be linked with the present program/channelin order to provide a complete 3D video service.

The linked_source_id indicates a source_id value of a channel includinga stream to be linked with the present program/channel in order toprovide a complete 3D video service.

Next, a signaling method using an SDT of DVB-SI will be described.

At a service level of the SDT, using the descriptor, information aboutenhancement data linked with a service specified by a service_id issignaled. This information indicates presence of data linked with theservice.

FIG. 11 is a diagram showing a syntax structure of an SDT including aservice_enhancement_descriptor( ) according to one embodiment of thepresent invention.

A table_id field is an 8-bit field and indicates that this sectionbelongs to a service description table.

A section_syntax_indicator field is a 1-bit field and the value thereofis set to 1.

A section_length field is a 12-bit field and the first two bits are 00.This field indicates the number of bytes of the section including CRCafter this field. The value of this field does not exceed 1021 and thetotal section length is a maximum of 1024 bytes.

A transport_stream field is a 16-bit field and serves as a label foridentifying a TS.

A version number field indicates is a 5-bit field and indicates theversion number of a sub_table. The value of this field is incremented byone whenever the sub_table is changed. If the version value reaches 31,a next version value becomes 0.

A current_next_indicator field has 1 bit and the value thereof is set to1 if a sub_table is currently applicable. If the value thereof is set to0, this indicates that the SDT is not applicable and a next table isvalid.

A section_number field has 8 bits and indicates the number of sections.A first section has a value of 0x00 and the value of this field isincremented by one whenever a section including the same table_id, thesame transport_stream_id and the same original_network_id is added.

A last section_number field has 8 bits and indicates the number of alast section (that is, a highest section_number) of the sub_table whichis a part of this section.

An original_network_id field is a 16-bit field and serves as a label foridentifying a network_id of a transmission system.

A service_id field is a 16-bit field and serves as a label fordistinguishing this service from another service included in a TS. Thisis equal to a program_number of a program_map_section.

An EIT_schedule_flag field is a 1-bit field, which indicates that EITschedule information for the service is currently included in a TS ifthe value thereof is set to 1 and indicates that EIT scheduleinformation for the service is not included in a TS if the value thereofis set to 0.

An EIT_present_following_flag field is a 1-bit field, which indicatesthat EIT_present_following information for the service is currentlyincluded in a TS if the value thereof is set to 1 andEIT_present_following information for the service is not included in aTS if the value thereof is set to 0.

A running_status field is a 3-bit field and indicates the status of theservice.

A free_CA_mode is a 1-bit field, which indicates that all elementstreams of the service are not scrambled if the value thereof is set to0 and indicates that one or more streams are controlled by a CA systemif the value thereof is set to 1.

A descriptors_loop_length is a 12-bit field, which indicates the totallength of the following descriptor in bytes.

A descriptor( ) includes a service_enhancement_descriptor( ) of thepresent invention.

A CRC_32 field is a 32-bit field, which indicates a CRC value for a zerooutput of a register within a decoder.

FIG. 12 is a diagram showing a syntax structure of aservice_enhancement_descriptor( ) according to one embodiment of thepresent invention.

The service_enhancement_descriptor includes a combined_service_type, anenhancement_type, an enhancement_right_flag, a sync_type, anenhancement_stream_format, an enhancement_stream_sampling_factor, alinked_TSID, a linked_original_network_id, a linked_service_alinked_elementary_PID, internet_linkage_information, a disparity_nearand a disparity_far.

The enhancement_type indicates the type of a path via which enhancementdata for the service is transmitted. For example, there are aterrestrial channel, the Internet, etc. The meaning of this field isequal to the above-described definition but is different therefrom inthat this field is applied in service units.

A linked_original_network_id indicates an original_network_id value of aservice including a stream to be linked with the present program/servicein order to provide a complete 3D video service.

A linked_service_id indicates a service_id value of a service includinga stream to be linked with the present program/service in order toprovide a complete 3D video service.

In the present embodiment, since the service_id field and theprogram_number field are included, the linked_program_number field isomitted. However, the linked_program_number field may be included in theservice_enhancement_descriptor.

Here, detailed information of a video stream corresponding to theenhancement data may be confirmed by referring to thecomponent_descriptor of the service or by checking a component_tag valueor an elementary PID value of the component added to theservice_enhancement_descriptor. That is, according to the embodiment, alinked_component_tag field or a linked_elementary_PID field of anassociated video/audio stream may be included in aservice_enhancement_descriptor and stream related information such as alinked_stream_content field and a linked_component_type field may alsobe included.

Alternatively, using a service level linkage_descriptor, informationabout enhancement data for the service may be signaled. In this case,information about the enhancement data linked with the service isincluded in the linkage_descriptor and the description thereof is equalto that of the service_enhancement_descriptor.

Next, a signaling method using an EIT of DVB-SI will be described.

At an event level of an EIT, using a descriptor, signaling ofenhancement data linked with this event is performed. The syntaxstructure of the EIT is slightly different from that of the EIT of theATSC PSIP.

FIG. 13 is a diagram showing a syntax structure of an EIT including anevent_enhancement_descriptor2( ) according to one embodiment of thepresent invention.

A table_id field is an 8-bit field and indicates that this sectionbelongs to a service description table.

A section_syntax_indicator field is a 1-bit field and the value thereofis set to 1.

A section_length field is a 12-bit field, which indicates the number ofbytes of the section including CRC after this field. The value of thisfield does not exceed 4093 and the total section length is a maximum of4096 bytes.

A service_id field is a 16-bit field, which serves as a label fordistinguishing this service from another service of a TS. The service_idhas the same value as the program_number of the program_map_sectioncorresponding thereto.

A version_number field indicates is a 5-bit field and indicates theversion number of a sub_table. The value of this field is incremented byone whenever the sub_table is changed. If the version value reaches 31,a next version value becomes 0.

A current_next_indicator field has 1 bit and the value thereof is set to1 if a sub_table is currently applicable. If the value thereof is set to0, this indicates that the SDT is not applicable and a next table isvalid.

A section_number field has 8 bits and indicates the number of sections.A first section has a value of 0x00 and the value of this field isincremented by one whenever a section including the same table_id, thesame transport_stream_id and the same original_network_id is added.

A last_section_number field has 8 bits and indicates the number of alast section (that is, a highest section_number) of the sub_table whichis a part of this section.

A transport_stream_field is a 16-bit field, which serves as a label foridentifying a TS.

An original_network_id field is a 16-bit field and serves as a label foridentifying a network_id of a transmission system.

A segment_last_section_number is an 8-bit field, which indicates thenumber of a last section of a segment of the sub_table. This field hasthe same value as the last_section_number field with respect to thesub_table which is not divided into segments.

A last_table_id is an 8-bit field, which indicates a last table_id.

An event_id value is a 16-bit field, which includes an id numberindicating the event (which is uniquely assigned in a servicedefinition).

A start_time field is a 40-bit field and indicates a start time of anevent in coordinated universal time (UTC) format or Modified Julian Date(MJD) format. This field includes 16 bits coded by 16 LSBs and 24 bitscoded by 6 digits of 4-bit binary coded decimal (BCD). If the start timeis not defined (e.g., NVOD service), all bits are set to 1.

A duration field is a 24-bit field and indicates the duration of anevent in hours, minutes or seconds. Accordingly, the duration isexpressed as 6 digits of 4-bit BCD and has 24 bits.

A running_status is a 3-bit field and indicates the status of an event.This field is set to 0 in case of an NVOD event.

A free_CA_mode is a 1-bit field, indicates that all element streams of aservice are not scrambled if the value thereof is set to 0 and indicatesthat one or more streams are controlled by a CA system if the valuethereof is set to 1.

A descriptors_loop_length field is a 12-bit field and indicates thetotal length of the following descriptor in bytes.

A CRC_32 field is a 32-bit field and indicates a CRC value for a zerooutput of a register within a decoder.

FIG. 14 is a diagram showing a syntax structure of anevent_enhancement_descriptor2( ) according to one embodiment of thepresent invention.

The event_enhancement_descriptor2( ) includes a combined_service_type,an enhancement_type, an enhancement_right_flag, a sync_type, anenhancement_stream_format, an enhancement_stream_sampling_factor, anavail_time_start, a linked_event_id, a linked_TSID, alinked_original_network_id, a linked_service_id,internet_linkage_information, a disparity_near and a disparity_far.

The components have been described above.

Information about the enhancement data of the event may be signaledusing a linkage_descriptor of an event level. In this case, informationabout enhancement data linked with the event is included in thelinkage_descriptor and includes the same content as theevent_enhancement_descriptor2( ).

Hereinafter, considerations for backward compatibility will bedescribed.

First, restrictions on a secondary channel service (enhancement(non-essential) channel/service) will be described.

In general, elements configuring a stereoscopic 3D video service receiveprimary video via an essential channel (legacy compatible channel) viawhich 2D video is received and acquire information about SI, etc. of theessential channel to access enhancement data based on this information.

Fundamentally, a channel for transmitting enhancement data cannotprovide an independent service and the following restrictions are set inorder to prevent malfunction of a conventional receiver.

In case of the ATSC TVCT, a service_type is set to 0x07 (parameterizedservice) or 0x0A (non-stand-alone type service carrying additionaldata).

A stream_type indicates depth/disparity data coded by AVC/H.264 anddepth/disparity data coded by MPEG-2. When specifying new a stream_type,the MPEG-2 registration_descriptor is used. For example, if thestream_type value of the depth/disparity data coded by AVC/H.264 is setto 0x83, the format_identifier field of the registration_descriptor hasa value of “DIS1”—(0x4449 5331) and the additional_idenfication_infofield has a value of 0x83.

In case of a DVB SDT/EIT, a service_type is set to 0x1F (non-essentialstereoscopic service carrying only additional/enhancement stream).

In case of stream_content and a component_type, a combination of thestream_content and the component_type of the existing high definitionvideo (MPEG-2 or H.264/AVC) is used or a combination for secondary videois newly defined.

FIG. 15 is a diagram showing a new combination of stream_content and acomponent_type according to one embodiment of the present invention. Ifthe stream_content is set to 0x01 and the component_type is set to 0x13,this indicates MPEG-2 video and depth/disparity map data and, if thestream_content is 0x05 and the component_type is set to 0x86, thisindicates H.264/AVC video and depth/disparity map data.

Hereinafter, when a path via which secondary video is received is anenhancement channel, a configuration method of this enhancement channelwill be described.

The enhancement channel is not recognized as a service channel or isignored by an existing receiver for compatibility with an existing HDreceiver and signaling may be configured so as not to be recognized as aservice by a 3D receiver. Secondary video is transmitted using suchenhancement channel. There are a method of inserting such secondaryvideo into a service recognizable by an existing receiver and requestingthat the secondary video should not be recognized and a method ofconfiguring and transmitting a transport stream such that the secondaryvideo cannot be recognized by the existing receiver.

First, a method of utilizing a separate (hidden) service will bedescribed.

In case of a method of inserting such secondary video into a servicerecognizable by an existing receiver and requesting that the secondaryvideo should not be recognized, signaling of FIGS. 16 and 17 isnecessary.

FIG. 16 is a diagram showing signaling for requesting that an existingreceiver should not recognize secondary video in an ATSC PSIPenvironment according to one embodiment of the present invention.

An enhancement channel activates a hidden bit of a TVCT to “1” andexcludes the hidden bit from a map of an existing receiver. During atest period, a hide-guide bit of the TVCT may be activated to “1” andmay be deactivated after standardization.

Signaling of a secondary video stream of a base channel (a channel viawhich primary video is received) may use a combination of a programnumber of a TVCT and a component type. As described above, alinked_program_number, a linked_tsid and a linked_elementary_PID may beused.

FIG. 17 is a diagram showing signaling for requesting that an existingreceiver should not recognize secondary video in a DVB-SI environmentaccording to one embodiment of the present invention.

In case of an enhancement channel, a hidden service is not explicitlysupported with respect to DVB-SI. Instead, an item corresponding to thehidden service is included in the standard of each country and thefunction thereof is activated such that the enhancement channel is notincluded in a channel map. In UK standard D-Book, if a numeric selectionflag and a visible service flag of a service attribute descriptorincluded in an NIT 2^(nd) loop is set to “0”, in the existing receiver,the channel is not displayed, is not selected using the numeral key ofthe remote controller and thus is not included in the channel map.

Signaling of a secondary video stream of a base channel may use acombination of an original network id, a transport stream id and acomponent type of an SDT. For example, a linked_original_network_id, alinked_tsid, a linked_service_id and a linked_elementary_PID may beused.

Next, a method of utilizing a separate (independent) component will bedescribed. If secondary video is transmitted so as not to be recognizedby an existing receiver, the following signaling is necessary.

FIG. 18 is a diagram showing signaling for preventing an existingreceiver from recognizing secondary video in an ATSC PSIP environmentaccording to one embodiment of the present invention.

FIG. 19 is a diagram showing signaling for preventing an existingreceiver from recognizing secondary video in a DVB-SI environmentaccording to one embodiment of the present invention.

In case of an enhancement channel, PSI information is limited to a PATin a TS. Thus, an existing receiver can detect a signal of this channelbut does not recognize the signal as a service and exclude the signalfrom the map. A program_loop is not present or program_number=0 is setsuch that the existing receiver cannot detect the signal. A program isnot present and only a network_PID is present.

In case of a base channel, signaling of a secondary video stream iscomposed of a combination of a transport_tream_id and a PID, forexample, a combination of the above-described linked_tsid and thelinked_elementary_PID. That is, in case of the enhancement channel, onlya secondary video stream is transmitted without a PMT.

Hereinafter, a synchronization method of a video signal and depthinformation (depth/disparity) will be described.

First, synchronization of a transport packet level will be described.

FIG. 20 is a diagram showing a transport_packet( ) according to oneembodiment of the present invention. A transport packet levelsynchronization method is a method of transmitting synchronizationinformation using an adaptation_field( ) of a transport packet. Atransport packet including a video component received via an existingchannel and a transport packet including enhancement data received via aseparate channel match or align so as to perform synchronization at atransport stream.

FIG. 21 is a diagram showing an adaptation_field( ) according to oneembodiment of the present invention. For synchronization, atransport_field_extension_flag of the adaptation_field( ) is set to 1and information regarding how many private_data_bytes are used issignaled using a transport_private_data_length. In addition, framenumber information of video/depth is signaled viavideo_frame_info_data_byte. A reception device controls synchronizationof elements configuring a 3D video service received via multiple pathsusing the above information.

FIG. 22(a) is a diagram showing the syntax of avideo_frame_info_data_byte according to one embodiment of the presentinvention. The video_frame_info_data_byte is located at aprivate_data_type of an adaptation_field of a transport packet and hasthe structure of FIG. 22(a). Here, the meaning of video_frame_info isdetermined according to the setting value of the frame_info_typeincluded in the video_frame_info_data_byte as shown in FIG. 22(b).

When the frame_info_type is 0x01, the video_frame_info means a decodingorder number. When the video_frame_info means the decoding order number,video decoding structures (GOP structures) of two components should bethe same.

When the frame_info_type is 0x02, the video_frame_info means a displayorder number. If the frame_info_type is 0x03, the video_frame_info meansa PTS value of a clock frequency of 90 KHz. Here, the PTS is anabbreviation for a presentation time stamp and indicates when a decodedaccess unit is reproduced.

If the frame_info_type is 0x04, the video_frame_info indicates anabsolute time of display. A most significant bit (MSB) of this field isset to and the number of remaining bits is 32 and the remaining bitsindicate a time in GPS seconds after 1980.1.6. 00:00:00 UTC.

If the frame_info_type is 0x05, the video_frame_info means a modifiedPTS. This is a time stamp related to the video_frame_info value of afirst picture in a video element set to 0. That is, the video_frame_infoof an individual picture is a relative count value according to adisplay time of a first picture of a video element. The unit of theabove count is equal to the period of a system clock of a frequency of90 KHz.

Next, a video level synchronization method will be described.

FIG. 23 is a diagram showing a video level synchronization methodaccording to one embodiment of the present invention. In case ofAVC/H.264 video, a video_frame_info_data_byte is transmitted in frameunits using an SEI message. Accordingly, a video_frame_info fieldincluded in a user_data_registered_itu_t_135 SEI message and avideo_frame_info field of an SEI message included in an AVC/H.264 videostream may match to perform synchronization of two streams. Forreference, an itu_t_35_country_code field and an itu_t_t35_provider_codefield use a value specified in the ITU-T T.35 recommendations andrespectively have 0xB5 and 0x0031 in case of ATSC.

In case of MPEG-2 video, the video_frame_info_data_byte is transmittedin a state of being included in picture user data.

Next, a system level synchronization method will be described.

In a system level synchronization method, synchronization is performedusing a PTS value included in a PES for an essential video stream (2Dimage) and a secondary video stream (enhancement stream). A method ofusing a PTS value is advantageous in that synchronization of independentelements received via a heterogeneous path while maintaining an existingspecification and is disadvantageous in that it is difficult to set acommon clock (PCR) for the PTS due to independent characteristics of theelements and the PTSs of the matching frames may not match even when thecommon clock is present. As a result, in regard to the PTS, even in theencoder, it is necessary to minutely synchronize two codecs. Inaddition, in case of non-real-time linkage, it is difficult to match thePTSs of a previously stored stream and a stream received in real time.

Next, operation of a reception device will be described.

FIG. 24 is a diagram showing a digital broadcast reception deviceaccording to one embodiment of the present invention. The digitalbroadcast reception device according to the present invention includes aplurality of system decoders 241 and 245, a plurality of video decoders242 and 246, a plurality of input controllers 243, 244 and 247, a viewsynthesizer 248, an output formatter 249 and an output controller 250.

Video decoding and synchronization and view synthesis for providing a 3Dvideo service using depth/disparity data will now be described. Thereception device extracts synchronization information from a 2D videosignal and a depth/disparity stream input to the system decoders 241 and245. Synchronization information may use 1) video_frame_info included ina transport packet, 2) video_frame_info included in an SEI message oruser data of a video stream or 3) a PTS value included in a PES packetheader as described above. The acquired synchronization information isused for matching of the 2D video signal and depth/disparity datadecoded independently decoded by the video decoders 242 and 246. In caseof 1) and 3), this information is acquired by the system decoders 241and 245 and is delivered to the input controllers 243 and 247 before theview synthesizer and, in case of 2), this information is acquired by thevideo decoders 242 and 246 and is delivered to the input controllers 243and 247 before the view synthesizer 248.

When video_frame_info is used to synchronize the components of 3Dstereoscopic video signal, output timing information of an actual imageuses an existing PTS value. That is, video_frame_info is used forsynchronization of two elements received via a heterogeneous path, andcontrol of output timing of an actual 3D view (other view synthesisusing 2D+enhancement data) and synchronization of a 3D view and an audiosignal is based on the PTS.

The view synthesizer 248 generates another view configuring astereoscopic 3D video signal using a 2D video signal and depth/disparitydata corresponding thereto. As a result, synchronization of the 2D videosignal and the depth/disparity stream should be performed just beforebeing input to the view synthesizer 248.

The secondary video (the right image or the left image) generated by theview synthesis and the primary video (the left image or the right image)received via the existing channel are output on the 3D display via theoutput formatter 249 as 3D video. Output timing of the 3D video iscontrolled based on the PTS by the output controller 250.

FIG. 25 is a diagram showing a view synthesis and synchronizationoperation according to one embodiment of the present invention. FIG. 25shows the order of generating the 3D video signal with lapse of timewhen a 3D video signal is provided using a 2D video signal and depthdata.

At t0, Frame 0 of a primary view is obtained via decoding of the 2Dvideo signal and depth information of Frame 0 is obtained via decodingof the depth data.

At t1, Frame 1 of a primary view is obtained via decoding of the 2Dvideo signal and depth information of Frame 1 is obtained via decodingof the depth data. Simultaneously, Frame 0 of a secondary view isobtained using Frame 0 of the primary view and depth information ofFrame 0 via the view synthesizer.

At t2, Frame 2 of a primary view is obtained via decoding of the 2Dvideo signal and depth information of Frame 2 is obtained via decodingof the depth information. In addition, Frame 1 of a secondary view isobtained using Frame 1 of the primary view and the depth information ofFrame 1 via the view synthesizer. Simultaneously, via the outputformatter, a formatting pair 0 which is a 3D video signal is obtainedusing Frame 0 of the primary view and the secondary view. Through such aprocess, it is possible to provide the 3D video signal to the user.

Finally, a method of receiving stereoscopic components at a receptiondevice will be described. A 2D video signal means a video signalreceived via an existing digital TV channel, which is encoded intoMPEG-2 video and may be encoded using AVC/H.264 or another codec. Amethod of receiving a 2D video signal is equal to an existing digital TVservice reception method. In this case, using an SI section received viathis channel, information about presence of enhancement data, asynthesis service format, a reception channel/path, an acquirable time,etc. is checked.

In the present invention, the enhancement data means depth map and adisparity map data. The enhancement data may include occlusion andtransparency information according to circumstance and may be referredto as a depth map for convenience. A 3D video signal reception devicesynthesizes a 2D video signal received via an existing channel andenhancement data to configure another view configuring a 3D stereoscopicvideo signal. In enhancement data, there are two methods such asreal-time linkage and non-real-time linkage.

First, in case of real-time linkage, enhancement data is received viathe Internet or another terrestrial channel together with a 2D videosignal received via an existing channel. At this time, the twocomponents are subjected to real-time reception and real-time decodingto provide real-time 3D video to the user.

In case of non-real-time linkage, enhancement data is previouslyreceived via the Internet or a terrestrial channel before a broadcasttime of a 2D video signal and is stored in a storage device. An NRTmethod and a method of recording live enhancement data are bothpossible. If a 2D video signal is broadcast via an existing channel, 3Dvideo is output via synchronization with the 2D video signal receivedwhile reproducing the pre-recorded/stored enhancement data. That is, anactual broadcast is a 2D live broadcast, but a receiver for pre-storingenhancement data may provide 3D video live.

When two or more enhancement data streams are transmitted, a depth rangesuitable for user preference may be selected using the disparity_nearand disparity_far field of each stream. That is, depth control may beimplemented via 3D rendering using the received map or selectivereception of multiple depth maps.

MODE FOR INVENTION

Various embodiments have been described in the best mode for carryingout the invention.

INDUSTRIAL APPLICABILITY

As described above, the present invention is wholly or partiallyapplicable to a digital broadcast system.

The invention claimed is:
 1. A digital broadcast signal processingmethod for providing stereoscopic three-dimensional (3D) video, thedigital broadcast signal processing method comprising: encoding a videostream of two-dimensional (2D) primary video; encoding a video stream ofsecondary video for generating binocular-parallax 3D video together withthe encoded video stream of the 2D primary video; generating firstsignaling information for the primary video and second signalinginformation for the secondary video; generating a first broadcast signalincluding the encoded video stream of the primary video and the firstsignaling information; generating a second broadcast signal includingthe encoded video stream of the secondary video and the second signalinginformation; and transmitting at least one of the first broadcast signalvia a first channel of a broadcast network and the second broadcastsignal via a second channel of the broadcast network, wherein the firstsignaling information includes enhancement type information indicatingwhether the secondary video is transmitted via the second channel of thebroadcast network or a broadband network, wherein the first signalinginformation further includes sync type information indicating whetherthe secondary video is transmitted in real time or in non-real time,wherein the second signaling information which is transmitted in thesecond broadcast signal via the second channel of the broadcast networkincludes first information indicating whether or not the secondary videois inactivated in a receiver.
 2. The digital broadcast signal processingmethod according to claim 1, wherein the second signaling informationfurther includes second information indicating whether or not the secondchannel appears in Electronic Program Guide (EPG) displays.
 3. Thedigital broadcast signal processing method according to claim 1, whereinthe generating the second signaling information includes generating thesecond signaling information for preventing a 2D video signal receiverfrom recognizing the encoded video stream of the secondary video.
 4. Thedigital broadcast signal processing method according to claim 3, whereinthe generating the second signaling information includes limiting thesecond signaling information of a stream transmitted by the secondbroadcast signal to only a PAT, and wherein the generating the secondsignaling information includes deleting a program_loop or setting aprogram_number to
 0. 5. A digital broadcast signal processing device forproviding stereoscopic three-dimensional video, the digital broadcastsignal processing device comprising: a first video encoder for encodinga video stream of two-dimensional (2D) primary video; a second videoencoder for encoding a video stream of secondary video for generatingbinocular-parallax 3D video together with the encoded video stream ofthe 2D primary video; an SI processor for generating first signalinginformation for the primary video and second signaling information forthe secondary video; a first system encoder for generating a firstbroadcast signal including the encoded video stream of the primary videoand the first signaling information; a second system encoder forgenerating a second broadcast signal including the encoded video streamof the secondary video and the second signaling information; and atransmission unit for transmitting at least one of the first broadcastsignal via a first channel of a broadcast network and the secondbroadcast signal via a second channel of the broadcast network, whereinthe first signaling information includes enhancement type informationindicating whether the secondary video is transmitted via the secondchannel of the broadcast network or a broadband network, wherein thefirst signaling information further includes sync type informationindicating whether the secondary video is transmitted in real time or innon-real time, wherein the second signaling information which istransmitted in the second broadcast signal via the second channel of thebroadcast network includes first information indicating whether or notthe secondary video is inactivated in a receiver.
 6. The digitalbroadcast signal processing device according to claim 5, wherein thesecond signaling information further includes second informationindicating whether or not the second channel appears in ElectronicProgram Guide (EPG) displays.
 7. The digital broadcast signal processingdevice according to claim 5, wherein the SI processor generates thesignaling information for preventing a 2D video signal receiver fromrecognizing the encoded video stream of the secondary video.
 8. Thedigital broadcast signal processing device according to claim 7, whereinthe SI processor limits the second signaling information of a streamtransmitted by the second broadcast signal to only a PAT, and whereinthe SI processor deletes a program_loop or sets a program_number to 0.